Package io.github.olyutorskii.aletojio.rng

Class RndAdapter

java.lang.Object

java.util.Random

io.github.olyutorskii.aletojio.rng.RndAdapter

All Implemented Interfaces:

RndInt31, RndInt32, RndInt64, Serializable

public class RndAdapter
extends Random
implements RndInt32, RndInt64, RndInt31

Random generator exchange adapter.

Designed to conserve as much random source entropy as possible.

Entropy is consumed first from MSB.

512 bits buffer is provided.

TODO: supporting java.util.random.RandomGenerator (JDK17 or later) and org.apache.commons.rng.UniformRandomProvider

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
RndAdapter(RndInt31 rndSrc)	Constructor.
RndAdapter(RndInt32 rndSrc)	Constructor.
RndAdapter(RndInt64 rndSrc)	Constructor.
RndAdapter(Random rndSrc)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected int	next(int bits)	Generates the next pseudorandom number.
boolean	nextBit()	Return next random number as 1bit boolean.
byte	nextByte()	Return next random number as 8bit byte.
int	nextInt31()	Return next random number as 31bit int from LSB without sign-bit.
int	nextInt32()	Return next random number as 32bit int with random sign-bit.
long	nextInt64()	Return next random number as 64bit long with random sign-bit.
void	setSeed(long seed)	Seed change is not supported.

Methods inherited from class java.util.Random

doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextBoolean, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

RndAdapter

public RndAdapter(RndInt32 rndSrc)
           throws NullPointerException

Constructor.

Parameters:

rndSrc - random generator

Throws:

NullPointerException - null argument

RndAdapter

public RndAdapter(RndInt64 rndSrc)
           throws NullPointerException

Constructor.

Parameters:

rndSrc - random generator

Throws:

NullPointerException - null argument

RndAdapter

public RndAdapter(RndInt31 rndSrc)
           throws NullPointerException

Constructor.

Parameters:

rndSrc - random generator

Throws:

NullPointerException - null argument

RndAdapter

public RndAdapter(Random rndSrc)
           throws NullPointerException

Constructor.

Parameters:

rndSrc - random generator

Throws:

NullPointerException - null argument

Method Details

setSeed

public void setSeed(long seed)
             throws UnsupportedOperationException

Seed change is not supported.

* However, it is allowed only during the initial constructor.

Overrides:

setSeed in class Random

Parameters:

seed - not supported

Throws:

UnsupportedOperationException - always

nextBit

public boolean nextBit()

Return next random number as 1bit boolean.

Unlike Random.nextBoolean() implement, any entropy from random source is not discarded.

Returns:

random number

nextByte

public byte nextByte()

Return next random number as 8bit byte.

Unlike Random.nextBytes(byte[]) implement, any entropy from random source is not discarded.

Returns:

random number

nextInt31

public int nextInt31()

Return next random number as 31bit int from LSB without sign-bit.

Only positive or zero value returned.

* LCG implementations on CPU without 64-bit remainders often output only 31-bit random numbers.

Entropy obtained from random source is returned without entropy missing.

Specified by:

nextInt31 in interface RndInt31

Returns:

random number

nextInt32

public int nextInt32()

Return next random number as 32bit int with random sign-bit.

Entropy obtained from random source is returned without entropy missing.

Specified by:

nextInt32 in interface RndInt32

Returns:

random number

nextInt64

public long nextInt64()

Return next random number as 64bit long with random sign-bit.

Entropy obtained from random source is returned without entropy missing.

Specified by:

nextInt64 in interface RndInt64

Returns:

random number

next

protected int next(int bits)

Generates the next pseudorandom number. Subclasses should override this, as this is used by Random original implementations.

* The original Random implementation often discards higher or lower bits of this return value.

Entropy obtained from random source is returned without entropy missing.

Overrides:

next in class Random

Parameters:

bits -

Returns: